The present invention claims priority from Japanese Patent Application No. 9-164473 filed Jun. 20, 1997, which is incorporated herein by reference.
1. Field of the Invention
The present invention relates to a container for liquids or powders which comprises an elastically deformable body and a valve provided in an opening of the body, and which is so constituted that small quantities of the contents held within the body can be discharged at a time from the valve by means of pressure applied to the body from the outside.
2. Description of Related Art
There are known containers having a valve in an opening in a container body holding the contents in liquid form. If the opening is turned to face downwards and the body is compressed by being manually squeezed, this valve is pushed open and a small quantity of the contents is discharged. If the force exerted by the hand is relaxed, the valve is pushed back by atmospheric pressure and thereby closes the opening. Once the valve has been pushed back by air pressure, if the opening is turned to face upwards and manual pressure is removed from the container, the valve is again opened by being pushed inwards by atmospheric pressure, whereupon air flows into the body and the shape of the body, having, been deformed by being squeezed, returns to its original shape. Such a container is also provided with a lid or cap on the outside of the valve, and is designed so that shutting this lid protects the valve with its delicate structure and stops air from flowing into or out of the container, thereby preventing its contents from deteriorating, with the result that they can be stored for a longer time. The container disclosed in Japanese Published Patent Application No. 6-59900 (hereinafter termed the prior art publication) is an example of this sort of container.
The inventors responsible for the present application have previously designed a container for liquid cleaning agents of relatively high viscosity. A container with the kind of valve described above is extremely convenient in that it enables a liquid cleaning agent to be dispensed in small quantities corresponding to the amount required, and in that the discharge of cleaning agent can be stopped by relaxing the manual force squeezing the container body. However, repeated tests brought to light the following shortcoming. Namely, the elastic synthetic resin which forms the valve adheres to itself at the slit of the valve, so that when the container is next used, the slit of the valve no longer opens and closes smoothly.